Multilayer PCBs would be AWESOME! I mean, 4 or 6 layers. Of course the price would be higher but over here a (ONE!) 6 layer 10x10cm PCB is hard to get under 200 Euros.
And (not concerning seeed in particular) the Open-Hardware scene (should we really call this a scene?) finally needs a revision management software. Like SVN. But what we need is a software that can handle both, code (all common languages INCLUDING VHDL/Verilog) and design files. As there are quite a lot of design tools out there the only way to manage PCB designs is by comparing and showing the gerber files while providing a download of both, gerber and system specific files.
For example someone designs an embedded system with a CPLD and a microcontroller. For the hardware design he uses Altium. Now he uploads the microcontroller code, the CPLD description files and the altium PCB file. ADDITIONALLY he uploads gerber files. Someone else downloads the altium file, changes something, uploads gerber and altium files again. Now the server compares the gerber files and shows differences online, but offers the altium file for download.
Oh, and of course we’d need a way to share and compare schematics. Is there a standard file format for schematics? I don’t think so 
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